Selective telephone system.



No. 779.982. PATENTED JAN. 10, 1905.

- P. J. ALBRECHT.

SELECTIVE TELEPHONE SYSTEM.

APPLICATION FILED JULY 25, 1904.

2 SHEETS-SEEET 1.

PATENTED JAN. 10, 1905.

P. J. ALBRECHT. SELECTIVE TELEPHONE SYSTEM.

APPLICATION FILED JULY 25, 1904.

2 SHEETS-SHEET 2.

NTTED STATES Patented January 10, 1905.

PATENT OFFICE.

SELECTIVE TELEPHONE SYSTEM.

SPECIFICATION forming part of Letters Patent No. 779,982, dated January10, 1905.

Application filed July 25, 1904. Serial No. 218,086.

To all whom it may concern.-

Be it known that I, PETER J. ALBRECHT, a citizen of the United States,residing at Marion, in the county of Turner, State of South Dakota, haveinvented certain new and useful Improvements in Selective TelephoneSysterns; and I do hereby declare the following to be a full, clear, andexact description of the invention, such as will enable others skilledin the art to which it ap pertains to make and use the same.

This invention relates to telephone systems, and more particularly tothe means for calling up the difierent subscribers on the line, theobject of the invention being to provide what is known as a selectivesystem, wherein any subscriber on a line may be rung up without ringingup the other subscribers.

A further object of the invention provides a system of this nature whichwill be cheap and simple and at the same time efiicient.

In the drawings forming a portion of this specification, and in whichlike characters of reference indicate similar parts in the severalviews, Figure 1 is a diagrammatic view showing a system embodying thepresent invention, the parts being in their inactive positions. Fig. 2is a view similar to Fig. 1, showing the parts in their activepositions.

Referring now to the drawings, there is shown a system including threesets of telephone instruments A, B, and C, each set of instrumentshaving a magneto, (indicated at D, E, and F, respectively.) In place ofthe usual magneto-bell in the ringingcircuit there is at each of thestations an electromagnet 5, 5', and 5", respectively, these magnets andthe magnetos being switched into and out of the talking-line in theusual manner, the specific switching mechanism for this purpose beingunnecessary to illustrate.

The equipment of each subscribers station is the same as that of everyother subscribers station, so that a description of one will suffice forthem all, there being one detail modified in each structure, which isthe location of the releasing-pin.

For purposes of convenience in description the parts at the station Awill be given basic numerals, while the parts at the station Ecorresponding will be given the same numerals with primes, while thesame numerals referring to like parts at station O will be givenseconds.

Referring then more particularly to station A, it will be noted thatthere is employed a common type of electric hell 6, which is in a localcircuit including a battery 7 and a pushbutton 8. A lever 9 is pivotedupon an upright 10, and at one end thereof is hung a weight 11, which issufficiently heavy to actuate the push-button 8 and close the circuit ofthe battery 7 when permitted to rest upon the push-button. The lever isheld normally with the weight 11 in raised or inactive position by meansof the retaining-pin 12 upon the face of the disk 13, which latter isprovided with a spring 14, which tends to rotate the disk and carry theretaining-pin from engagement with the lover. The disk 13 is heldnormally against rotation under the influence of the spring 14 by meansof the latch-lever 15, having a terminal hook 16, which engages the lug17 on the periphery of the disk. A helical spring 18, connected to thelatch-lever 15 and to the post 19, on which it is pivoted, holds thelatch lever normally and yieldably in engaging position.

To actuate the lever 15 and release the disk 13, an actuating-disk 20 isprovided, having a helical spring 21,which tends to rotate the disk. Apin 22 is engaged in the periphery of the disk 20, and When the disk isrotated under the influence of its spring the pin 22 is carried againstthe adjacent end of the latch-lever 15 and moves it, with its hook, fromengagement with the lug 17. In the periphery of thehub 23 of the disk 20is a notch 2 with which normally engages an arm 25 to hold the diskagainst rotation.

The disk 20 has trunnions 26, which are mounted in journal-boxes at theends of a pivoted yoke 27, the disk being movable with the yoke to carryit away from the arm 25, so as to disengage the arm from the notch 24,the

attract the armature 30, carried by the yoke 27, to draw the yoke, withthe disk, into disengaged position when the magnet is energized. Theelectromagnet 5 is one member of a relay comprising an armature-lever31, which when the magnet 5 is energized is moved into contact with thepoint 32, so as to close the local circuit of a battery 33, whichcircuit includes the magnet 29.

With, the construction described it will be seen that as soon as themagnet 5 is energized the disk 20 is drawn downwardly to disengage thearm 25, which latter is of spring material. .As soon as the disk 20 isdrawn down it begins to rotate, and when it is released and rises itcontinues to rotate until the notched portion of the hub reaches the arm25 again, when the disk stops. The pin 22 is of such length that whenthe disk is drawn downwardly it will not strike the latch-lever 15, andconsequently said lever is only actuated when the disk is inraisedposition. It will be noted that the pins 22, 22, and 22" of theseveral stations are different angular distances from the notches 2st,24, and 2a, respectively. WVhen, therefore, it is desired to sound thebell 6 at the station A, the calling-magneto is operated to quicklyrelease the disk 20 and then return it to permit its pin 22 to strikethe latch-lever 15 and then to operate the magneto again until the pins22 and 22 have passed their respective latch-levers 15 and 15". Each ofthe disks 20, 20, and 20 is provided with a governor, which may be inthe form of a pendulum 3 L, these pendulums being set to operatesubstantially in unison, so that the disks move substantially in unison,and each operator by Watching his own disk is enabled to tell thepositions of the other disks and when to operate his magneto to obtainthe desired results.

it will be understood that in practice modifications of the specificconstruction shown may be made and any suitable materials andproportions may be used for the various parts without departing from thespirit of the in- Vention.

What is claimed is- 1. In a selective telephone system, the combinationwith a plurality of stations each having a relay in its ringing-circuit,of a local circuit at each station controlled by the relay, a localsignal-circuit at each station, means for closing the signal-circuit,means for releasing the closing means, means for actuating the releasingmeans, means for holding the releasing means normally inactive and withrespect to which said releasing means is movable into and outofengagement with the holding means, and an electromagnet in thesecondary circuit of the relay and under the influence of which theactuating means is movable out of engagement with the holding means, theactuating means being adapted for successive operation.

2. In a selective telephone system, the combination with a plurality ofstations each having a relay in its ringing-circuit, of a localsignal-circuit at each station including a pushbutton, means foractuating the push-button, a lever connected with thepush-button-actuating means, a rotatable disk, a pin carried by the diskand disposed to engage and hold the lever with the pushbutton-actuatingmeans inactive, means for rotating the disk with its pin out ofengagement with the lever, a latchlever disposed to hold the disknormally against rotation, a second rotatable disk at each station,means for rotating the second disk, means for holding the second disknormally against rotation, a radial pin upon the periphery of each ofthe second disks, said pins having different positions upon thedifferent disks and adapted to engage their respective latch-levers andmove them to inactive positions when their respective second disks arerotated, and electromechanical means in the secondary circuit of eachrelay for shifting the corresponding second disk out of engagement withits holding means, at which times said pins are movable free from thelatch-levers.

3. In a selective telephone system, the combination with a plurality ofstations each having a relay in its ringing-circuit, of a local circuitat each station controlled by the relay, a local signal-circuit at eachstation, means for closing the signal-circuit, means for releasing theclosing means, means for actuating the releasing means, means forholding the releasing means normally inactive and with respect to whichsaid releasing means is movable into and out of engagement with theholding means, an electromagnet in the secondary circuit of the relayand under the influence of which the actuating means is movable out ofengagement with the holding means and out of active relation to thereleasing means, and means for returning the actuating means to itsnormal position when the influence of the electromagnet is removed.

In testimony whereof I affix my signature in presence of two Witnesses.

PETER J. ALBRECHT.

Witnesses:

H. VAN RUsoHEN, JAKoB ALBRECHT.

